Principles of designing for the bicycle

John FranklinCycling Skills & Safety Consultant

Core principles

• Conservation of momentum• Even surfaces• Maximise visibility• Personal space• Secondary defence• Make it legal

Conservation of momentum

• Each stop = 100 metres travel• Each person has optimum rate of pedalling• Direct, easy routes that minimise stopping and

accommodate likely speeds

TYPICAL CYCLING SPEEDS(on the level)

Sports cyclist 20 – 30+ mph

Confident commuter 15 – 20 mph

General utility /commuter

10 – 15 mph

Children 10 – 20 mph

Leisure rider 10 – 15 mph

Even surfaces

• Poor surfaces destroy momentum• Comfort and safety considerations

Observation and Visibility

• Looking ahead easy (eye movement)• Looking behind more difficult (head movement)

and less stable

Observation and visibility

• A common cause of crashes

Personal space• For comfort and safety• To provide margin for

‘drift’ and error

Personal space

Personal space

More space needed if:• Traffic speeds > 30mph• High-sided vehicles• Strong wind or heavy rain

Personal space

Secondary Defence

• No-one should be hurt because they make a single error of judgement

Make it legal